Control device



y 22, 1945- M. o. BASSETT 2,376,652

CONTROL DEVICE Filed Nov. 20, 1943 In ventor:

w? a m Mm W1 0 A m MW Patented May 22, 1945 um'rso (stares PATENT OFFICE con'rnonnnvrcn v Merton o. Bassett, Schenectady, N. Y., assignor to General Electric Com New York may, a corporation of Application November 20, 1943, Serial No. 511,053

- 5 Claims. (01. 200-106) My invention relates to control devices, more particularly to electromagnetically latched motor starting switches, and has for its object a simple, reliable and inexpensive electromagnetic motor starter which is shockproof.

When an electromagnet is subjected to shocks with its armature in its attracted position, the armature, if the shock is severe enough, is

thrown from its attracted position against the holding force of the mas'net.- I have found that .when the magnet is pivotally mounted, the force of the shock produces oscillation of the magnet on its pivot without throwing the armature from its attracted position. In fact, I have found that wih-such a mounting a relatively small amount of power supplied to the magnet is suflicient to hold the armature in its attracted position against a of a switch of the type described and claimed in U. S. Patent 2,291,466, issued on July 28, 1942, to Leon J. Goldberg; This switch is provided with an arc chute member 10, held in place by knobs Ila and Illb, which encloses stationary and movable contacts (not shown). The movable contacts are' n'ounted on a rotatable member or shaft vii made of a molded electrically insulating material and mounted for rotation 'on bearing posts 12 and I3 secured to a suitable panel support i4. The shaft H is turned to close and open the switch by means of an arm very severe shock whereas when the anagnet is' I mounted solidly on a support, the coil cannot in some cases be energized strongly encugh to hold the armature in its attracted position because the m net structure becomes saturated before egoufih pull is developed to resist the force of the 3 0C x In carrying out my invention in one form I provide a holding electromagnet which, under normal conditions, is energized thereby to hold its armature in an attracted position, the armature in turn maintaining'the switch in a closed position. In accordance with my invention, I mount the holding magnet and its armature on a pivot for movement in response to shocks and provide. a latching portion on the armature which, with the armature in its attracted position, has its latching surface for holding the-switch closed lying on the pivot axis of the magnet. With this arrangement, when the device is subjected to shocks, the magnet is free to move about its pivot but in doing so does not move the latching surface of the armature, since that surface lies on the pivot axis, and therefore maintains the switch in its latch closed position.

For a more complete understanding of'my in- I vention, reference should be had to the accom-. panying drawing in which Fig. 1 is a front elei5 secured to the shaft'adiacent the bearing post it, this arm and the shaft being turned clockwise from the position shown in Fig. 2 by press ing manually a, button It toward the right hand; as seen in Fig. 2.

As shown most clearly. in Fig. 3, the button it is on the end of a link n slidably mounted in a member 18 mounted {on one arm' I! of a U-shaped support 20 having a.}second arm 2|, this support being secured to the'panel ll, At its lower end the link I1 is pivotally connected at 22 with an arm 23 having one end mounted on a stationary,

pivot 24 and its other end pivotally connected at 25 to a link 26. The upper end of the link 26 is pivotally secured to a rod 21 which in turn is connected to a latch and cam operating or control member made in two identical parts 28 and 29.

These two parts 28 and 29, are secured rigidly together in slightly spaced parallelrelation with each other by the rod or bolt 21 so that together they constitute a latch and cam member. They are pivotally mounted on a rod 20 mounted on the arms 19 and 2|. Between these two members 28, 29 extends the lower end of the arm- I! which carries a. pin or bolt 2| extending at its opposite ends through cam slots 32 and 32 in the members.

These cam slots are identical in shape and size. They extend in-such directions with respect to the pivot shaft 20 that when the latch member 20, 28 is moved on the pivot shaft, the end of the arm I! is moved with repsect to the pivot shaft thereby to turn the shaft II and operate the switch. Thus the upper ends of the-slots are quite near the pivot shaft l0 and theslots extend in parallel relation with each other away from the pivot shaft. with the switch in its tripped-open position shown in Fig. 2, when the button is is depressed the cam member 28, 2! is turned clockwiseon the pivot shaft it through the linkage 23, 2. and the operating pin 21. This movement causes the lefthandwalls of the slots, as seen in Fig. 2. to engage and pushthe pin it away from e. magnet provided with oneness spring means for holding end electromngn predetermined normal loosition about said axis thereby to provide for oscillation of said ele'ctroniosnet about said axis in the event oi n sh applied to said device, letchinsg moons on ereted by said armature for engaging said com trol. member when said armature is in its attracted ;position at a point lying substantially on said ends thereby to hold said control member in said second position, and means biasing said armature to on unattracted position to release said control member when said electromas'net n deener sized.

33. A control device comprising a switch, means for moving said switch to a closed circuit position, e magnet provided with on armature mounted for movement between attracted and unottracted 90-.

sitions, a latching member for holding said switch in its closed position engaging said armature tel-mined latching position when said armature is in one oi'said positions, 7

and means pivotelly mountingsaid magnet for oscillatory movement about a. pivot axis passing through the point of engagement of said latchin; member with said armature.

4.- A control, device comprising a, switch, means for moving said switch to a closed circuit position, a pivotally mounted armature, latching means for holding said switch in its closed position engaging one end oisaid I armature when said armature is. in its attracted titre.

5. The combination with e. movable member of nosition, and moons nivoteilx; mount said magnet for oscillatory movement ebout e pivot axis psesins through the point of eneegemeni of said latching member with said end of said arms shockproof latching means therefor comprising. a support, pivot mounting means for said support providing on axis about which support is lili= balanced, resilient means for holding; said sonnets in a. predetermined normal similar position about said axis thereby to provide for oscillation oi sold rtebont said axis in the event of e emailed to said mounting means o latch member for said movable member inovebly mounted on said support, and holding me on said support for maintaining said latch member in a, prede- V relative to said support and for cilecting movement of said latch member to release said movable member, said latch member being provided with a, latching our. face for engagement with said movable member lying substantially on said pivot axis or said support when said latch member is in said predetermined latching position so that said oscillation of said support about said axis is ineflective to re lease ssid latch member from said movable morn- 

